Moving alog to bigger projects with more power consumption I began to read more on properly powering the Arduino, however I still wonder about what the right way in certain situations is.
Arduino Mega + Multiple modules, LCD, sensors + serial communication with PC over USB port
I need to power many peripheral devices that require a 5V supply or reference voltage and I don't want to overload the onboard 5V voltage supply. I could use an external 5V regulator and connect all my devices and the Arduino 5V pin to this supply to bypass current away from the Arduino's onboard voltage regulator.
However, I read that powering Arduino through the 5V pin is a "dangerous game" with zero tolerance for mistakes. Some suggest using the USB port to supply the 5V, but I am already using it for serial communication.
Moreover, I read that Arduino automatically switches from USB to "Jack" power supply if detected, which is not the case on the 5V pin. What would happen if I had a USB and a 5V power supply connected at the same time?
To sum up: Any suggestions on how to simultaneously do the following 3 things: - USB serial communication - Power the Arduino - Have an external 5V reference/supply voltage that bypasses the onboard regulator and is identical to the 5V pin on Arduino